20 October 2001, 08:46
RobgunbuilderOversize firing pin in .17 Rem
Anybody have any success in using an oversize firing pin ( Holland) in a .17 Rem to reduce cratering? I put a 32# spring in mine and it helps but doesn't totally resolve the problem. My gun was built on a Rem 700 action that was a .223 before it became a .17 and I believe the cratering is due to a sloppy fit between the factory firing pin and the bolt hole. I've tried different primers and they all crater. It's not due to overpressure!
20 October 2001, 16:28
<Dan C>I have the Holland pin in my 19-223 Calhoon, fitted within .002" to the hole, and it craters as bad as ever. The solution is to bush the firing pin hole in your bolt and use a .062" firing pin. The smaller pin has less surface area for the primer to flow against......less cratering. Gre-Tan Rifles does this mod for $40, and it works. The phone # is 970.353.6176
Dan C
20 October 2001, 18:03
Kevin GulletteYep! As usual, Dan is correctamundo.
The bushed firing pin hole is 40% smaller in area.
The cratering IS from pressure......A "focused" pressure of a relatively small bore, in combination with a relatively large flash hole.
Friend Of The 17,
Kevin Gullette